Log to Firefox Error Console from JavaScript

Is it possible to add messages to the built-in error console of Firefox from JavaScript code running in web pages?

I know that I there's Firebug, which provides a console object and its own error console, but I was looking for a quick fix earlier on and couldn't find anything.

I guess it might not be possible at all, to prevent malicious web pages from spamming the log?

If you define a global function that checks for the existence of window.console, you can use Firebug for tracing and still plays nice with other browsers and/or if you turn Firebug's console tracing off:

debug = function (log_txt) {
    if (typeof window.console != 'undefined') {
        console.log(log_txt);
    }
}

debug("foo!");

You cannot write to the console directly from untrusted JavaScript (e.g. scripts coming from a page). However, even if installing Firebug does not appeal to you, I'd recommend checking out Firebug Lite, which requires no installation into the browser (nor, in fact, does it even require Firefox). It's a script which you can include into any web page (even dynamically), which will give you some basic Firebug functionality (such as console.log()).

Yes, you can =P

function log(param){
    setTimeout(function(){
        throw new Error("Debug: " + param)
    },0)
}

//Simple Test:
alert(1)
log('This is my message to the error log -_-')
alert(2)
log('I can do this forever, does not break')
alert(3)

Update to a real function

This is a simple hack, just for fun.